Dietary omega-3 fatty acids partially correct the enhanced in vivo uptake of glucose in diabetic rats.

This study was undertaken to determine the effects of feeding isocaloric semisynthetic diets high in saturated fatty acids from beef tallow (BT) or high in polyunsaturated fatty acids from fish oil (FO), on the clinical control and the in vivo uptake of varying concentrations of D-glucose into perfused jejunal and ileal loops of intestine of rats with streptozotocin diabetes. Jejunal and ileal weights were greater in diabetic than in control rats fed BT or FO, but the percentage of the intestinal wall comprised of mucosa was lower, resulting in a similar mass of mucosa in diabetic and in control animals. Feeding FO increased the jejunal unstirred water layer (UWL) resistance in control rats but decreased ileal UWL in diabetic animals; UWL was lower in diabetic than in control rats fed FO but was similar in those fed BT. The passive permeability coefficient (Pd) of the intestine for L-glucose was greater in diabetic than in control rats fed BT but not in those fed FO; Pd was higher in control rats fed FO than BT. The maximal transport rate (Vmax) and Michaelis constant (Km) of jejunal D-glucose uptake were lower in control rats fed FO than BT. Jejunal Vmax was lower in diabetic than control rats fed BT, yet was higher for those fed FO. The ileal Vmax for D-glucose uptake was greater in diabetic than in control animals fed BT or FO.(ABSTRACT TRUNCATED AT 250 WORDS)